Kanye West posted a photo of Florida shooting survivor Emma Gonzalez on Twitter and called her his "Hero". The teen activist responded with her own hero - a man who is credited with saving lives in a shooting in a Waffle House in Nashville on 22 April. Emma has become a key figure in the Never Again movement, which was started after 17 people died in a school shooting in Florida in February. Emma came to prominence in February when she gave a powerful speech "Calling BS" on gun culture in the US. The 18-year-old goes to Marjory Stoneman Douglas high school in Parkland, Florida, which was the scene of a shooting on Valentine's Day. Last Sunday, a naked gunman burst into a Waffle House restaurant in Nashville, Tennessee, and killed four people.